Thermostatically controlled mixing valve for sanitary devices

ABSTRACT

This invention refers to a thermostatically controlled mixing valve for a sanitary installation. The mixing valve is provided with a chamber for mixing the hot and cold water. The mixing chamber has disposed therein, temperature sensing means which automatically adjusts the amount of hot and cold water entering therein to the pre-set temperature and also serves as an outlet which is coupled to a consumption or use point. The mixing valve is provided with either a cartridge which includes valve means for opening and closing the hot and cold water supply with means for proportioning the amount of hot and cold water entering the mixing chamber or a cartridge which includes means for proportioning the amount of hot and cold water entering the mixing chamber with automatic built-in back flow prevention valves for the hot and cold water supply; both cartridges being replaceable or interchangeable respectively within the housing of the mixing valve.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a division of application Ser. No. 833,931, filed Sept. 16,1977, now U.S. Pat. No. 4,121,761, which in turn is a continuation ofapplication Ser. No. 677,574, filed Apr. 16, 1976, now abandoned.

BACKGROUND OF THE INVENTION

Two types of thermostatically controlled mixing valves are generallyemployed in sanitary installations. One type, hereinafter referred to asan individual thermostat, includes a volume regulating assembly whichfunctions as a shut-off valve that opens and closes the hot and coldwater supply to the valve and also controls the temperature discharge ofthe water. The other type, hereinafter referred to as a centralthermostat, includes only a temperature regulating mechanism withautomatic one way valve means which prevents the back flow of hot andcold water through the potable water system. The valve for opening andclosing the temperature regulated water passing through the mixing valveis located at or near a use point. Thermostatically controlled mixingvalves of the type described are published in German patent applicationsNo. P 23 55 100.0 published May 15, 1975 and No. P 23 55 101.1 publishedMay 15, 1975.

Individual thermostats differ from central thermostats in that thetemperature and volume of the water can be adjusted by a volume controlassembly mounted within the valve body whereas in the centralthermostat, only the temperature of the water can be adjusted. Thedesired volume of water passing through a central thermostat is adjustedby means of separate shut-off valves provided at one or more of the usepoints.

One of the disadvantages of thermostatically controlled mixing valves ofeither the individual or the central types is that the essentialelements of one mixing valve type cannot be combined with the essentialelements of the other type. Also, it is not possible, for example, torebuild a mixing valve of the central thermostat type into mixing valveof the individual type without replacing the entire thermostaticallycontrolled mixing valve.

SUMMARY OF THE INVENTION

One of the prime objects of the present invention is to provide a novelconstruction for utilizing either the individual or the central typethermostatically controlled mixing valve bodies or housings and convertthem to either a central or an individual type mixing valve without thenecessity of removing the entire valve assembly and housing from thesanitary installation.

It is another object of the invention to provide a cartridge arrangedand constructed having the elements of either an individual or centraltype mixing valve so that either cartridge may be utilized within thestandard valve housing or body of conventional thermostaticallycontrolled mixing valves having a single thermostatic element, forexample, a U-shaped bi-metallic element. The cartridges are so designedthat their external dimensions are identical to the spaces formed in thehousing so that they may be inserted therein by simple threadedengagement.

The invention generally contemplates providing a thermostaticallycontrolled mixing valve adapted for use in sanitary installations. Themixing valve comprises a valve body having hot and cold water inletopenings and an outlet opening. The valve body is formed having a firstchamber communicating with the outlet opening and has mounted therein atemperature sensing assembly. A second chamber which communicates withthe hot and cold water inlet openings and the outlet opening, is formedin the valve body and is disposed normal to the first chamber. Thesecond chamber is arranged and constructed of a size adapted to receivea cartridge assembly of the type having a temperature and volume controlassembly or a temperature controlled assembly only. The temperaturesensing assembly is operatively coupled to the temperature controlassembly of either type of cartridge so that water entering the firstchamber is mixed to a desired pre-set temperature.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a longitudinal elevational view partly in section of one formof a thermostatically controlled mixing valve of the central type;

FIG. 2 is a longitudinal elevational view partly in section of thecartridge assembly of FIG. 1;

FIG. 3 is another form of thermostatically controlled mixing valvehaving the identical body of FIG. 1 and cartridge assembly of theindividual type; and

FIG. 4 is a longitudinal elevational view of the cartridge assembly ofFIG. 3.

DESCRIPTION OF PREFERRED EMBODIMENT

Referring to FIG. 1 numeral 1 designates a concealed box foraccommodating the central thermostat which may be used as a temperaturecontrolling means for a number of outlets for example for both the bathand shower outlets. The housing of the mixing valve or valve bodyincludes elements 2 and 3. Element 2 forms a mixing chamber 4 and at thesame time serves as the outlet opening for the temperature controlledwater. Element 3 disposed transversely to mixing chamber 4 isdimensioned to receive a regulating mechanism or assembly in the form ofa compact unit or cartridge 11 shown most clearly in FIG. 2. It shouldbe noted that element 3 is dimensioned so as to be adapted to receivenot only the cartridge 11 of FIG. 2 but also cartridge 11' of FIG. 4without any modification to the valve body or housing 3.

U-shaped bi-metallic element 5 is disposed in mixing chamber 4 and ispart of the temperature sensing assembly that engages the temperaturecontrolling mechanism of cartridge 11. The temperature controllingmechanism includes control sleeve 10 which is slidably mounted oncartridge 11 and moves against the resistance of spring 9. Arm 7 ofbimetallic element 5 engages collar 8 formed between the ends of controlsleeve 10 so that a change in water temperature will cause the shiftingof control sleeve 10 against spring 9. The other arm 14 of bi-metallicelement 5 forms a stop for plunger 15 which is movable axially inresponse to a desired temperature setting. Spring 16 and plunger 16' aremounted in element 2 of the valve body and is displaceable against themovement of plunger 15. It can be seen that by adjusting the temperaturesetting handle 33 to the desired temperature, plunger 15 will moveaxially either inwardly or outwardly as the case may be thereby causingcontrol sleeve 10 to shift to and away from the hot and cold waterentering openings 25 and 24 respectively of cartridge 11. Plunger 15passes through an opening formed in arm 7 and is loaded by spring 16through plunger 16' which is retained in a screw threaded sleeve 18formed in the rear wall 17 of housing or element 2 of the mixing valve.

Control sleeve 10 through bi-metallic element 5 is adjustable andcontrols the amount of hot and cold water flowing into mixing chamber 4.When hot water is required, bi-metallic element 5 forces control sleeve10 toward valve seat 22 so that edge 19 of control sleeve 10 will seatand shut off the cold water flow so that only hot water passes intomixing chamber 4. Conversely when more cold water is required controlsleeve 10 moves away from valve seat 22 by the action of bi-metallicelement 5 and spring 9 so that end surface 20 of control sleeve 10 willseat on surface 23 of cartridge housing 21.

Cartridge housing 21 contains one-way valves 26 and 27 which are mountedon cartridge 11 at the ends of control sleeve 10 and behind cold waterentry opening 24 and hot water entry openings 25. Head member 30 formedat the outer end of cartridge 11 includes collar 28 and projections 29which mount in place one way valve 26 so that cold water will only flowinto cartridge 11. Collar 31 formed at the other end of cartridge 11 andprotruding thread ring 32 of cartridge housing 21 mounts hot waterone-way valve 27 so that only hot water will flow into cartridge 11.Both one-way valves 26 and 27 are shown most clearly in FIG. 2 and arenormally closed by the action of springs 26' and 27' and will only openthrough water pressure exerted against the inlet side of each valve.

Temperature setting handle 33 is mounted for rotation on cartridge 11and is preferably made of plastic material. Rated value ring 34 isthreadedly mounted on element 3 of the mixing valve and is coupled totemperature setting handle 33. Plunger 15 is spaced parallel tocartridge 11 and is actuated by face 35 of rated value ring 34 and isshiftable axially to and away from arm 14 of bi-metallic element 5 whentemperature setting handle 33 is rotated. When rated value ring 34 isrotated clockwise plunger 15 is pressed against arm 14 by camming actionof face 35 and shifts plunger 16' to cause the hot water entry opening25 to be closed by control sleeve 10. Conversely, as rated value ring 34is rotated counterclockwise, the pressure on plunger 16' is released andcauses plunger 15 to shift away from arm 14 so that cold water entryopening 24 will be closed by control sleeve 10. Plastic scale ring 36having temperature indicia imprinted thereon is mounted on temperaturesetting handle 33. Temperature scale ring 36 may be fixed in placeeither by a pressure fit or by welding. Anti-scald means in the form ofa limit button 37 is operatively mounted on temperature setting handle33.

Rated value ring 34 and temperature setting handle 33 are coupledtogether through interior ring collar 39. Ring collar 39 is weldedaround its periphery to temperature setting handle 33 and is providedwith a plurality of transverse openings 40. This assembly is thencoupled to rated value ring 34 by threaded screw 41 through opening 40as shown in FIG. 1. When the thermostatically controlled mixing valve isready for use it may be necessary to calibrate the discharge watertemperature to correspond to the temperature indicia on temperaturesetting handle 33. This is accomplished by removing threaded screw 41and shifting temperature setting handle 33 either clockwise orcounterclockwise on rated value ring 34 until the discharge watertemperature corresponds to the temperature indicia on handle 33. Whenthis has been completed screw 41 is threaded back into rated value ring34 through opening 40. In this regard the number of transverse openings40 formed in interior ring collar 39 do not correspond to the number ofthreads formed on rated value ring 34. It has been found advantageous toprovide three spaced transverse openings 40 in interior ring 39 and toprovide a quadruple thread in rated value ring 34. This will permitadequate adjustment of discharge water temperature to correspond withthe temperature indicia on the temperature setting handle.

Limit button 37 cooperates with a stop or adjusting ring 42, retained athead member 30 forming one end of the cartridge and which seals theholding space or chamber of element 3 of the mixing valve body. Stopring 42 is provided with a counter-marking to the temperature scale 36,and is partially or completely slotted to provide ease for mounting onhead member 30. Serrations or grooves 44 are formed on head number 30 toobtain a better clamp connection when screw 43 is mounted in adjustingring 42 as shown in FIG. 1. A terminal cap 46 is held in place by acenter screw threaded into head member 30.

Limit button 37 cooperates with stop ring 42 so that an outlet watertemperature of 40° C. maximum is provided during normal operation. If ahigher outlet water temperature is desired, limit button 37 is depressedto permit temperature setting handle 33 to be turned to the left asviewed in FIG. 1 to a maximum rated value for example, 70° C. Plunger 15is moved downwardly against thermostat arm 14 which compresses spring 16and in turn causes the thermostat arm to push upwardly against stop 8thereby closing the cold water entry valve 26 which permits a greaterproportion of hot water to enter mixing chamber 4. When temperaturesetting handle 33 is turned to the right again toward normal operation,limit button 37 automatically returns to its normal position by means ofspring 47. Subsequently when the mixing valve is used again, thetemperature setting handle cannot be turned to a temperature settinggreater than 40° C. without again depressing limit button 37.

As shown in FIGS. 1 through 4, cartridges 11, 11' have a plurality ofO-rings 48 which provide for liquid tight sealing of the different partsof the valve or cartridge. Face or escutcheon plate 49 and slottedterminal sleeve 50 cover the opening in the wall so that a greateresthetic or pleasing external finish is provided. Escutcheon plate 49contacts the wall, not shown, and is held on mixing valve housing by oneor more screws 51. Slotted terminal sleeve 50 can be adjusted fordifferent depths of wall thickness by simply removing part of the sleeveat the slotted or grooved areas. The slotted terminal sleeve 50 is incontact with locking pin 52. The rear wall 53 of box 1 may beconstructed so that plaster can be applied thereto particularly wherethe box may protrude through a narrow partition wall.

Referring to the embodiment shown in FIGS. 3 and 4, cartridge 11' hasidentical external dimensions to that of cartridge 11 so that cartridge11' can be mounted in liquidtight engagement in the chamber or holdingplace of element 3 of the mixing valve. Cartridge 11' is arranged andconstructed having the same temperature controlling elements ofcartridge 11 but does not include one-way valves 26 and 27. Cartridge11' is utilized for mixing valves of the individual type and includeshot and cold water volume control means. A rotatably mounted axial shaft60 extends the entire length of cartridge 11' and functionsindependently to the temperature controlling means of the mixing valve.Shaft 60 has mounted thereon spaced hot and cold water shut-off valves61 and 62. Mounted on the outer end of the shaft is volume controlhandle 68 which is used for opening and closing the hot and cold watervalves simultaneously. Cold water valve 61 has mounted on its lowerface, O-ring 63 which seats against surface 64 of cartridge housing 21'.Hot water valve 62 similarly has resilient O-ring 65 mounted on itslower face which engages surface 66 to form a watertight seal in theclosed position as shown in FIG. 4. When cartridge 11' is mounted invalve housing 3, as in FIG. 3, the temperature sensing and actuatingmechanisms operate identical to the temperature sensing and actuatingmechanism shown in the mixing valve of FIG. 1 since the parts utilizedare identical and therefore need not be described in this embodiment.When the thermostatically controlled mixing valve of FIG. 3 is beingoperated, the volume control handle 68 is turned counterclockwise toopen the hot and cold water supply simultaneously. The temperaturesetting handle is turned to the desired temperature indicia thereon sothat the discharge water from chamber 44 will correspond to thetemperature indicia on the temperature setting handle 33.

The embodiment of FIGS. 3 and 4 differ from the embodiment of FIGS. 1and 2 in that the mixing valve of FIGS. 3 and 4 includes hot and coldwater shut-off means which acts independently with the temperaturesensing and controlling means of the mixing valve. Also this type ofmixing valve, of the individual type, does not require one-way valves asback flow preventers since the valve includes hot and cold watershut-off means. In the embodiment of FIGS. 1 and 2, the mixing valvedoes not provide an independent means for controlling the hot and coldwater flowing through the valve but only controls the temperature. Themixing valve also includes one-way valves to prevent back flow of waterthrough the valve in the event there is a reduced pressure experiencewithin the water supply system.

Both cartridges 11 and 11' include fine mesh screens 55 at the hot andcold water inlet openings of the cartridge to screen out any coarsegrains of sand that may be entrained in the water. It is also apparentthat cartridges 11 and 11' are interchangeable and may be utilized inthe same mixing valve housing when so desired. It is obvious that thepresent design permits the removal of cartridges 11 or 11' without thenecessity to remove thermostat 5 from chamber 4.

Many modifications of design and use of different materials arecontemplated without departing from the invention as claimed herein.

What is claimed is:
 1. In a thermostatically controlled mixing valve, acartridge adapted to be removably insertable into a valve body so as toprovide either an individual or a central type thermostaticallycontrolled mixing valve for use in sanitary installations, said valvecomprising:a valve body having an outlet opening, hot and cold waterinlet openings, and having a first chamber in fluid communication withsaid outlet opening and a second chamber; a temperature sensing andthermostat control assembly mounted in said first chamber; said secondchamber being selectively in fluid communication with said hot and coldwater inlet openings, said second chamber being disposed normal to saidfirst chamber so as to removably receive a cartridge in liquid tightengagement; said cartridge comprising a volume control assembly whichincludes a rotatably mounted shaft extending along the axial lengththereof, spaced hot and cold water valve means mounted on said shaft sothat when said shaft is rotated to its on and off positionsrespectively, said hot and cold water valves open and closesimultaneously; a temperature control sleeve and collar assemblyoperatively coupled to and engaged with said temperature sensing andcontrol assembly so that said temperature sensing and control assemblyis independently operable with said volume control assembly; saidtemperature sensing and control assembly having a U-shaped bimetallicelement mounted in said first chamber; a first arm of said bimetallicelement forming a stop for a first plunger; a second arm of saidbimetallic element biasing against a shoulder on said temperaturecontrol sleeve; a second plunger in said valve body which moves axiallyin response to a temperature setting of said temperature sensing andcontrol assembly; a second independent spring mounted in said valve bodywhich is displaceable against the action of said first plunger tothereby cause said sleeve to shift to or away from the hot and coldwater outlet openings of said cartridge in response to a temperaturechange in the water in said first chamber; and said cartridge assemblyhaving its external dimensions identical to the space in said secondchamber so as to be insertable alternately, into said second chamber ofsaid valve body of either an individual or central type thermostaticallycontrolled mixing valve.